During the production and processing of stainless steel heat exchange tubes, cracks appear on the surface, so what are the main reasons for this? How should we solve it?
Zhejiang Mingxin Stainless Steel Co., Ltd. is a modern stainless steel pipeline system manufacturing enterprise integrating scientific research, production and sales. The company adopts advanced, efficient and mature production management mode. Leading materials for the production of high-quality stainless steel, to provide reliable and safe stainless steel pipes and pipe fittings for global users.
1. Exposure to chloride
Stainless steel heat exchange tubes are in contact with various chlorides or chloride-containing solutions, nitric acid, nitrate, hydroxide, hydrofluoric acid, hydrogen sulfide aqueous solution, polythionic acid, sulfuric acid and sulfurous acid, etc., which will cause stress corrosion , resulting in cracking.
2. Residual stress
The residual stress of the material produced by the stainless steel heat exchange tube during welding, heat treatment and thermal processing, as well as the assembly stress during installation, the pressure difference between the inside and outside of the tube and the temperature difference during work will all produce mechanical stress and thermal stress, which will lead to stainless steel heat transfer. The tube generates tensile stress. The greater the residual stress, the more prone to stress corrosion cracking of stainless steel heat exchange tubes.
Approach:
If you want to solve the cracking of stainless steel heat exchange tubes, you need to start from the stress, transportation medium and working conditions, such as:
1. Stress concentration and gap generation should be avoided, and the welding process should be improved.
2. Strictly control the water quality conditions. When the Cl- concentration and oxygen content increase and cannot be reduced within a few hours, the equipment should be stopped immediately.